The present invention relates to apparatus for shaping exposed surfaces of a product (for example, for shaping the exposed top surface of a stick product, such as an antiperspirant/deodorant stick product), methods of shaping such surfaces of such products, and the products produced. More particularly, the present invention is directed to an apparatus and method for shaping the exposed top end of an oval cross-section stick product (e.g., an elongated (elliptical) antiperspirant/deodorant stick product) so as to have a compound curve shape, contoured in two separate directions (e.g., a domed shape).
It is desirable to produce stick products, such as (but not limited to) antiperspirant/deodorant or other cosmetic and toiletry products, having a top surface (to contact selected parts of a human body) in a form or shape adapted to comfortably apply the product to selected parts of the human body. For example, it is desirable to produce antiperspirant/deodorant products having a top surface with a shape to substantially conform to the axillary region.
Solid forms of antiperspirant or deodorant products are generally produced by molding a liquid composition into a solid stick form having a variety of cross-sections (e.g., casting the liquid composition into a dispenser shell which is the barrel of the product package); in the presently popular elongated stick deodorant, the solid stick form has an oval or elliptical cross-section. The stick is molded within the dispenser shell which defines the cross-section of the product, with some mechanism being provided for advancing the stick from the shell so as to expose the top end of the stick, and for retracting the stick after use.
The dispenser shells may be filled using either a top-fill or a bottom-fill method. In the top-fill method, the product container shell is entirely assembled except for the cap, and liquid product is poured into the container from the top and hardens or cures into the supporting platform which is already inserted in the bottom of the dispenser shell.
A problem with stick products as molded in this manner is that, as molded, the end of the molded product, e.g., to contact the body during application of a deodorant, does not have a desired shape. With a stick product made utilizing the above-referred-to top-fill method, producing a desired shaped end (to contact the body during application) requires trimming or cutting the end of the solidified product into the desired shape. With cylindrical antiperspirant sticks having a circular cross-section, the exposed end may be trimmed using, for example, an arrangement of hemispherically shaped cutting edges revolving about the cylindrical axis. However, it is more difficult to easily shape the end of a top-filled product if the cross-section of the solid stick form is oval, elliptical or anything other than circular.
European Patent Application No. 335,112 (hereinafter "EPA 335,112"), the contents of which are incorporated herein by reference in their entirety, discloses a method and apparatus for trimming into a desired shape the end of a solid cylindrical form, which can be utilized where the cross-section of the solid stick form is oval, elliptical or any other form, including circular. Specifically, in the disclosed process and apparatus the packaged products having exposed end portions desired to be shaped are provided at a product working station, each product working station having a shaping device. Each shaping device comprises at least a pre-cut member and a finish cut member (in one embodiment, the shaping device includes a pre-cut member and two finish cut members). Initially, the pre-cut member is rotated in a first direction about an axis through an arc sufficient to cause the pre-cut member to cut through one edge of a respective product to be shaped at a respective work station. Thereafter, the finish cut member (or members) is rotated (through an arc) in the opposite direction to that in which the pre-cut member was rotated, to provide an exposed end of the product having the desired final shape. Each of the pre-cut and finish cut members have blades with a pre-determined profile in a direction perpendicular to the arcuate path, to contour the product in the direction perpendicular to the arcuate path. The excess material trimmed from the end of the product falls into a reclaiming tray for re-use or discard. During the cutting of the product to shape the end, the individual packaged products are held stationary; thereafter, the individual products are removed from the work stations, and replaced by new packaged products to be cut to have a desired end shape. Thus, in EPA 335,112 the products whose surfaces are to be shaped are held stationary during shaping, the packaged products being treated in a batch process.
Various problems arise in connection with the method and apparatus disclosed in EPA 335,112. For example, since the European patent application discloses a batch process, the apparatus and method described therein are not conducive to performing and providing continuous treatment of stick product, e.g., on a continuous conveyancing system. Furthermore, since the cutting members disclosed in the European patent application have a single arcuate path, the apparatus and method in the European patent application cannot be utilized to provide different shapes for the exposed end of the product, e.g., in the direction of the plane containing the arcuate path; and, moreover, cannot be used to achieve a shaped end having different radii of curvature in a single direction (e.g., having different radii of curvature at the leading and trailing edges of an elliptical stick product, in the direction of the major axis of the ellipse, as compared with the radius of curvature at a central portion of such elliptical product in the direction of the major axis). Moreover, the structure and method in EPA 335,112 is relatively complex, requiring movement of a plurality of cutting blades in opposite arcuate directions.
Accordingly, it is desired to provide a method and apparatus for shaping the top surface of a packaged product (for example, a stick product, such as an antiperspirant or deodorant stick product) with a compound shape, using a simple technique, and which facilitates a continuous process.
In the following description, the present invention will be described in terms of shaping an antiperspirant or deodorant stick product for application to axillary regions of the human body. However, the present invention is not so limited, and, as can be appreciated, the present invention can be applied to other solid products (solid articles of manufacture), including other stick products for application to the human body (e.g., insecticide sticks); or, more generally, to any solid article of manufacture wherein an exposed end thereof is to be shaped.